Private fields are not private.

[stevenbey]

When declaring a private field, the resulting JavaScript is:

var Example;
(function (Example) {
    var Test = (function () {
        function Test() {
            this._value = 0;
        }
        Object.defineProperty(Test.prototype, "value", {
            get: function () {
                return this._value;
            },
            enumerable: true,
            configurable: true
        });
        return Test;
    })();
    Example.Test = Test;
})(Example || (Example = {}));

However, this means that private fields are visible when inspecting the object (e.g. using the console.dir method) and, therefore, aren't truly private.

I suggest moving the declaration of private fields to the scope of the containing anonymous function:

var Example;
(function (Example) {
    var Test = (function () {
        var _value = 0;
        function Test() {
        }
        Object.defineProperty(Test.prototype, "value", {
            get: function () {
                return _value;
            },
            enumerable: true,
            configurable: true
        });
        return Test;
    })();
    Example.Test = Test;
})(Example || (Example = {}));

[RyanCavanaugh]

See existing issues #1537 and #564